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Note 3 - Loans Receivable and Allowance for Credit Losses on Loans - Schedule of Modified Financing Receivables (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
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Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Commercial Real Estate Portfolio Segment [Member] | Commercial Loan [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.70% | 0.60% | 1.10% | 0.60%
Commercial Real Estate Portfolio Segment [Member] | Commercial Loan [Member] | Extended Maturity and Payment Delay [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 1,202 | $ 1,116 | $ 1,202 | $ 1,116
Commercial Real Estate Portfolio Segment [Member] | Commercial Loan [Member] | Extended Maturity [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified, Weighted Average Term Extension Payment Delay (Year) | 3 years | 2 years | 3 years | 2 years
Commercial Business Portfolio Segment [Member] | Commercial And Industrial [Member] | Principal Forgiveness [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified in Period, Amount | $ 260 |  | $ 260 |
Financing Receivable, Excluding Accrued Interest, Modified in Period, to Total Financing Receivables, Percentage | 0.10% |  | 0.10% |
Financing Receivable, Excluding Accrued Interest, Modified, Increase (Decrease) from Modification |  |  | $ 357 |
Commercial Business Portfolio Segment [Member] | Commercial And Industrial [Member] | Principal Forgiven [Member] |  |  |  |
Financing Receivable, Excluding Accrued Interest, Modified, Increase (Decrease) from Modification | $ 357 |  |  |

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- Definition Period of increase in weighted average maturity of financing receivable modified (excluding accrued interest) for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days + References No definition available. + Details
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- Definition Amount of increase (decrease) in amortized cost excluding accrued interest, of financing receivable modified for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
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- Definition Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
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- Definition Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-42 + Details
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